ESTRO 37 Abstract book

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ESTRO 37

ICS3 were all obviously superior than ICS1 for all these three plannings 。 Moderate positive correlation was founded between Dmean for IMC and Dmean for heart for patients underwent CRT (r=0.338, P=0.01). Whereas for F-IMRT and I-IMRT groups, positive correlation were founded between Dmean for IMC and Dmean and V 20 for ipsilateral lung. Conclusion The Dmean to IMC was 32.85 Gy for all patients, and the dose delivered to IMC showed no difference in CRT, F- IMRT and I-IMRT(33.80 Gy, 29.65 Gy and 32.95 Gy). For the IMC dose in the first three intercostal spaces (ICS1-3), there were no difference to the three treatment plannings. The Dmean,V 20 ,V 30 ,V 40 and V 50 of the ICS2 and ICS3 were all obviously superior than ICS1 for all these three plannings 。 Moderate positive correlation was founded between Dmean for IMC and Dmean for heart for patients underwent CRT (r=0.338, P=0.01). Whereas for F-IMRT and I-IMRT groups, positive correlation were founded between Dmean for IMC and Dmean and V 20 for ipsilateral lung. EP-1311 Self-reported work ability in breast cancer patients during and after breast cancer treatment. M. Gregorowitsch 1 1 UMC Utrecht, Radiation Oncology, Utrecht, The Netherlands Purpose or Objective Early detection and advances in breast cancer treatment has led to an improved survival. As a result understanding the long-term effects of various breast cancer treatments is important. Returning to work after treatment and maintaining employment is relevant, since work is intrinsically rewarding, an important source of income and generates social interactions. Knowledge of disease characteristics and treatment factors associated with poor work ability allows adequate information of patients on what to expect and to offer targeted interventions. This may contribute to improved quality of life (QoL) after breast cancer treatment. Material and Methods This study was conducted within the Dutch UMBRELLA cohort, i.e. prospective observational cohort including breast cancer patients indicated to receive post- operative radiotherapy at the department of Radiation Oncology at the University Medical Centre Utrecht. All working-aged breast cancer patients (<67 years) within the Dutch UMBRELLA cohort were selected. Work ability and QoL were measured by the Work Ability Index (WAI) [Ilmarinen J, 2007] and EORTC QLQ-C30 questionnaire, respectively. The WAI score, ranging from 7 to 49, was calculated. Higher scores reflect better work ability and scores were categorized in low (7-36) and good/excellent (37-49). Mean work ability scores were stratified for treatment strategies and compared with scores of the age-matched Dutch reference population. Results Between October 2013 and November 2016, 844 patients were enrolled. In total 527 patients (62%) responded to at least one of the questionnaires and were employed at the time of assessment. Of the responders, 65% had permanent employment, 14% were freelancer, 9% had temporary contracts and 12% reported another form of employment. Mean age of the study population was 52 years. At baseline, before start of radiotherapy, the mean WAI score was 30.8, which was substantially lower than the reference population score of 42. Low work ability at baseline was reported by 68% (n=360) of the patients. At 6 and 18 months, mean work ability scores increased to 33.2 and 37.5, resp. and the proportion of patients with suboptimal work ability decreased over time (60% at 6 months and 36% at 18 months). Patients who reported a low work ability at baseline were significantly younger (51 years vs. 53 years in patients

generated through recombination of 2D maps. Using the AHA 17 segment model[3] (excluding segment 17 (apical cap)), segmental peak 2D/3D longitudinal, circumferential, and radial strain was measured with MRI tissue tracking software (cvi42, v4.5, Circle software). Corresponding RT doses to the AHA LV segments were determined from contours outlined in the cardiac axes in Oncentra Brachytherapy v4.5.2, before being imported into Mim v6.77(Mim Software) for dosimetric readout. Paired t-tests were performed between pre and post RT measurements for each segment, with a p<0.05 considered significant. Correlations between delta-strain values and radiation dose were performed, a p<0.05 being significant. Results The average mean heart dose was 2.39Gy (1.38-3.42). On average, 2D short axis circumferential strain was reduced in segments 1 (-23.57% vs -19.13% p=0.05) and 14 (- 23.50% vs -17.93% p=0.05). 3D circumferential strain was affected in segments 7 (-19.17% vs -16.39% p=0.02), 8 (- 20.67% vs -18.73% p=0.05) and 13(-18.48% vs-15.95% p=0.02). 3D radial strain was reduced in segments 8 (35.32% vs 25.46% p=0.02) and 9 (27.24% vs17.54% p=0.03). 3D longitudinal strain was reduced in segment 7 (-21.43% vs -19.12% p=0.03) only. There was a statistically significant negative correlation between dose and △ strain in segments 12 and 14 corresponding to mid anterolateral and apical septal walls. Statistically significant mixed negative and positive correlations between dose and △ strain were seen in segment 6 (basal anterolateral segment). Table 1 provides detailed segmental △ strain and dose correlations. A representative scatter plot of delta strain and dose is shown in Fig. 1. Conclusion Tangential left sided breast RT may result in early cardiac dysfunction. Preliminary analysis suggests a mixed but predominant negative correlation of LV segmental △ strain with dose following tangential radiotherapy, occurring predominantly in the antero- lateral wall of the LV and apical septal segment. EP-1310 Breast irradiotion using three techniques: evaluate the dose distribution in internal mammary chain W. Wang 1 , L. Jianbin 1 , S. Yuanfang 1 , X. Min 1 , S. Qian 1 , Z. Yingjie 1 , L. Xijun 1 , L. Fengxiang 1 1 Shandong cancer hospital affiliated to Shandong University, Radiation Oncology, Jinan, China Purpose or Objective To evaluated the unplanned coverage dose to the internal mammary chain (IMC) in patient treated with radical mastectomy or modified radical mastectomy, and its relation with the type of the treatment planning. Material and Methods One hundred and thirty eight patients undergoing RT in our hospital for breast cancer were retrospectively analyzed. Patients were divided into three groups: three- dimensional conformal radiotherapy (3D- CRT) group, forward intensity-modulated radiotherapy (F- IMRT) group and inverse IMRT (I-IMRT) group. The IMC were contoured according to Radiation Therapy Oncology Group (RTOG) concensus,and were not include into the planning target volume (PTV).The mean doses ( D mean) and the volumes receiving equal or more than 20 Gy, 30 Gy, 40 Gy, 50 Gy (V 20 , V 30 , V 40 , V 50 ) to IMC were analyzed. Results The Dmean to IMC was 32.85 Gy for all patients, and the dose delivered to IMC showed no difference in CRT, F- IMRT and I-IMRT(33.80 Gy, 29.65 Gy and 32.95 Gy). For the IMC dose in the first three intercostal spaces (ICS1-3), there were no difference to the three treatment plannings. The Dmean,V 20 ,V 30 ,V 40 and V 50 of the ICS2 and